John Prescott was facing court action today by the country's biggest rail union which wants to repossess a cut-price flat it has let to the Deputy Prime Minister for more than 30 years.

The RMT is seeking to redevelop a site at Clapham, south London, which includes a first-floor flat rented by Mr Prescott at a reduced rate. The union, which aims to build social housing, has offered the Deputy Prime Minister an alternative flat and believes it has respected his legal rights.

Mr Prescott pays &#xA3;220 a month for the two-bedroom property, which estate agents believe would fetch &#xA3;1,600 if let commercially.

Mr Prescott has not commented publicly on the issue and the union would only say today that it was a private matter.

But one well placed RMT source said: "Mr Prescott left the union last year on a point of principle. It's a pity he did not apply the same principle to his cheap flat.

"We have members who are cleaners on less than &#xA3;4.50 an hour being balloted for industrial action against a 2% pay offer. Why should they be expected to subsidise cheap accommodation for someone on &#xA3;140,000 a year?"